Re: [Qemu-devel] [RESEND PATCH v3 4/8] qdev: Add memory hot unplug support for bus-less devices.

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 27 Aug 2014 16:08:35 +0800
Tang Chen <tangchen@cn.fujitsu.com> wrote:

> From: Hu Tao <hutao@cn.fujitsu.com>
> 
> Implement bus-less device hot-remove in qdev_unplug(). It will call PCMachine
> callback introduced in previous patch.
> 
subject/commit message doesn't need to mention memory hotplug/PCMachine,
it's generic handling that applies to other devices even though
pc-dimm is the only bus-less device handled here.


> Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
> ---
>  hw/core/qdev.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/hw/core/qdev.c b/hw/core/qdev.c
> index da1ba48..e365a74 100644
> --- a/hw/core/qdev.c
> +++ b/hw/core/qdev.c
> @@ -228,6 +228,14 @@ void qdev_unplug(DeviceState *dev, Error **errp)
>  
>      if (dev->parent_bus && dev->parent_bus->hotplug_handler) {
>          hotplug_handler_unplug(dev->parent_bus->hotplug_handler, dev, errp);
> +    } else if (*errp == NULL) {
what's the reason for ^^^ condition here?

> +        HotplugHandler *hotplug_ctrl;
> +        MachineState *machine = MACHINE(qdev_get_machine());
> +        MachineClass *mc = MACHINE_GET_CLASS(machine);
> +
> +        hotplug_ctrl = mc->get_hotplug_handler(machine, dev);
> +        if (hotplug_ctrl)
> +            hotplug_handler_unplug(hotplug_ctrl, dev, errp);
>      } else {
>          assert(dc->unplug != NULL);
>          if (dc->unplug(dev) < 0) { /* legacy handler */